At Trent Bridge, Brad Haddin’s valiant attempt to win the match was terminated by an inside edge. He was not given out by umpire Aleem Dar, but although Hot Spot was inconclusive, the sound of ball on bat was enough to convince the third umpire Marais Erasmus to overturn the verdict and England were victors by 14 runs.

At Lord’s, there were three balls remaining of the fourth day when Australia’s last man, James Pattinson, appeared to snick Graeme Swann to Matt Prior. The batsman reviewed it, Hot Spot again showed nothing but Hawk-Eye indicated that if there was no bat involved he was lbw, so the decision stood. England were 2-0 up, a critical advantage which has enabled England to retain the urn quicker than at any time in Ashes history.

These were two of a litany of incidents which, however, betrayed the limitations both of the decision-making technology and the umpires’ interpretation of it, a situation the players are increasingly seeking to exploit. Hot Spot is the main culprit. The four infra-red cameras around the ground are there to detect the friction between leather and willow when a ball has been edged.

They are effective when the edge is quite substantial, but slow-motion cameras usually pick up these anyway. Problems arise when the edge is thin and the bat speed is considerable. The wind created by a flashing blade dissipates the thermal particles that form a ‘hot spot’ and the infra-red cameras suggest no contact. This also tends to be true on a hot day when the air around the bat is already warm and the friction-generated ‘heat’ of an edge is undetectable.

Players are well aware of this and the general levels of confusion among third umpires and frequently feign innocence when they snick the ball imagining they will get away with it. They often do. Steve Smith was clearly out caught behind driving at James Anderson in Australia’s first innings at Old Trafford.

But Hot Spot showed nothing and the third umpire Kumar Dharmasena did not have the confidence to overturn the not out decision on the basis of sound evidence only.

Similarly on Monday, Kevin Pietersen obviously edged a loose waft against Peter Siddle which this time the umpire heard. A slight pause before reviewing betrayed Pietersen’s guilt. Again Hot Spot showed nothing but this time the third umpire agreed that the sound was enough to convict him. That has to be the way forward.

Hot Spot just tends to confuse the issue, regularly giving batsmen an alibi. Until its sensitivity is improved it should be withdrawn, leaving umpires to use those old-fashioned assets their eyes and ears to make the judgment.

Changes are afoot in the DRS world. Currently the third umpire sits in his own eyrie overlooking the ground with a couple of small TV monitors. When an incident needs to be reviewed, he is fed appropriate replays by the television director. The process is still flawed and slow and the sound feed is of negligible quality.

Finally realising this the ICC experimented with an idea at Old Trafford that I first suggested about a decade ago when working for Channel 4. Umpire Nigel Llong sat in a transit van behind the media stand with his own videotape operator manning a giant screen showing eight camera angles simultaneously.

A delivery could be instantly replayed from any chosen angle, magnified, slowed or frozen. A clean feed from the stump microphones is also broadcast through a large speaker.

The system is completely independent of the TV coverage. A clear decision on what had actually happened could be made in the time it takes for the batsman or captain to call for a review (15 seconds.)

Llong agreed this system was much more efficient and was confident that the right decision would be made faster and more often. He did concede that specialist third umpires who are properly trained in how the technology works might be an advantage, and less injustices would result.

Before that happens batsmen will be keener than ever to abide by that old adage: "If you’re going to flash, flash hard."